Solve for $x$ : $9\sqrt{x} + 9 = 3\sqrt{x} + 3$
Solution: Subtract $3\sqrt{x}$ from both sides: $(9\sqrt{x} + 9) - 3\sqrt{x} = (3\sqrt{x} + 3) - 3\sqrt{x}$ $6\sqrt{x} + 9 = 3$ Subtract $9$ from both sides: $(6\sqrt{x} + 9) - 9 = 3 - 9$ $6\sqrt{x} = -6$ Divide both sides by $6$ $\frac{6\sqrt{x}}{6} = \frac{-6}{6}$ Simplify. $\sqrt{x} = -1$ The principal root of a number cannot be negative. So, there is no solution.